1. Field of the Invention
The invention relates to a shaped sheet laminate, a method and a shaping apparatus for manufacturing the shaped sheet laminate.
2. Description of the Related Art
A commercial absorbent article such as a disposable diaper, a sanitary napkin and so forth usually includes a surface layer for contacting human skin and guiding fluids discharged from human body to keep human skin dry and comfortable. Referring to FIGS. 1 and 2, U.S. Patent Application Publication No. 2010/0249740 A1 discloses a shaped sheet laminate 1, which is adapted for an absorbent article as a surface layer and has an uneven surface structure. As shown in FIG. 1, the shaped sheet laminate 1 includes a plurality of indented portions 11, a plurality of projection portions 14, and a plurality of first and second connection portions 12 and 13. For further understanding the structure of the shaped sheet laminate 1, FIG. 2 is a pattern chart that depicts a six-point embossing pattern of the shaped sheet laminate 1 in a coordinate system, wherein α represents the indented portion 11, β represents the projection portion 14, γ represents the first connecting portion 13, and ε represents the second connecting portion 12. It is shown in FIGS. 1 and 2 that the indented portions 11 are separated from each other by respective projection portions 14 and first and second connecting portions 12 and 13, which results in weak fluid distribution between the indented portions 11 when the fluid is flowing on the indented portions 11, thereby reducing the absorbing effect of the absorbent article.
Further, the shaped sheet laminate 1 is manufactured using a first roller, a second roller, and a third roller cooperating with each other to bond a top sheet and a bottom sheet together, thus forming the shaped sheet laminate 1. The first roller is made of several gears parallel arranged on a rotating shaft, and the adjacent gears are combined such that their tooth pitches are offset by 0.5 pitch. The second roller has similar configuration with the first roller while gear teeth of the second roller mesh with those of the first roller. The third roller is in rolling contact with the first roller and capable of being heated. While manufacturing the shaped sheet laminate 1, the top sheet passes through a first nip zone defined by the first and second rollers to form a projection-indentation structure, followed by delivering the bottom sheet together with the top sheet to pass through a second nip zone between the first roller and the third roller, so as to bond the top sheet and the bottom sheet to form the shaped sheet laminate 1.
However, it is time consuming to assemble the first and second rollers, since the gears of the first and second rollers are required to remain in the specific configuration.